Siemens 7SG23 MSCDN - MP2A User manual

Reyrolle
Protection
Devices
7SG23 MSCDN – MP2A
Capacitor Unbalance Protection
Answers for energy

7SG23 MP2A MSCDN Contents
The copyright and other intellectual property rights in this document, and in any model or article produced from it
(and including any registered or unregistered design rights) are the property of Siemens Protection Devices
Limited. No part of this document shall be reproduced or modified or stored in another form, in any data retrieval
system, without the permission of Siemens Protection Devices Limited, nor shall any model or article be
reproduced from this document unless Siemens Protection Devices Limited consent.
While the information and guidance given in this document is believed to be correct, no liability shall be accepted
for any loss or damage caused by any error or omission, whether such error or omission is the result of
negligence or any other cause. Any and all such liability is disclaimed.
©2010 Siemens Protection Devices Limited
Contents
Technical Manual Chapters
1. Description of Operation
2. Performance Specification
3. Relay Settings
4. Communications
5. Applications
6. Installation
7. Commissioning
8. maintenance
9. Diagrams

MSCDN – MP2A Description of Operation
The copyright and other intellectual property rights in this document, and in any model or article produced from it
(and including any registered or unregistered design rights) are the property of Siemens Protection Devices
Limited. No part of this document shall be reproduced or modified or stored in another form, in any data retrieval
system, without the permission of Siemens Protection Devices Limited, nor shall any model or article be
reproduced from this document unless Siemens Protection Devices Limited consent.
While the information and guidance given in this document is believed to be correct, no liability shall be accepted
for any loss or damage caused by any error or omission, whether such error or omission is the result of
negligence or any other cause. Any and all such liability is disclaimed.
©2010 Siemens Protection Devices Limited
MSCDN – MP2A
Capacitor unbalance protection
Document Release History
This document is issue 2010/02. The list of revisions up to and including this issue is:
Pre release
2010/02 Document reformat due to rebrand
23/01/2003 R1 First version
Software Revision History
26/02/2006 2621H80002R9

MSCDN – MP2A Description of Operation
Contents
1Introduction .............................................................................................................................................................. 3
2Hardware Description............................................................................................................................................... 3
2.1 General.......................................................................................................................................................... 3
2.2 Analogue Inputs............................................................................................................................................. 4
2.3 Status Inputs.................................................................................................................................................. 4
2.4 Output Relays ................................................................................................................................................ 4
2.5 Fascia LEDS.................................................................................................................................................. 4
2.6 Self Monitoring............................................................................................................................................... 4
2.6.1 Protection Healthy/Defective.................................................................................................................. 5
3Protection Functions ................................................................................................................................................ 5
3.1 Resistor R1 and R2 Thermal Overload (R1 49, R2 49) ................................................................................. 5
3.2 Resistor R1 and R2 Open Circuit (50OC)...................................................................................................... 5
3.3 Trip Circuit Supervision.................................................................................................................................. 6
4Other Features......................................................................................................................................................... 6
4.1 Metering......................................................................................................................................................... 6
4.2 Data Storage ................................................................................................................................................. 6
4.2.1 General.................................................................................................................................................. 6
4.2.2 Waveform Records. ............................................................................................................................... 6
4.2.3 Event Records ....................................................................................................................................... 6
4.2.4 Fault Recording ..................................................................................................................................... 7
4.3 Time Synchronisation .................................................................................................................................... 7
4.3.1 IRIG-B Time Synchronisation ................................................................................................................ 7
4.3.2 IEC 60870-5-103 Time Synchronisation ................................................................................................ 7
4.3.3 Real Time Clock Time Synchronisation ................................................................................................. 7
4.4 Communications ............................................................................................................................................ 7
4.5 Settings Groups............................................................................................................................................. 7
4.6 Password Feature.......................................................................................................................................... 8
5User Interface .......................................................................................................................................................... 8
5.1 Liquid Crystal Display .................................................................................................................................... 8
5.2 Back light Control........................................................................................................................................... 8
5.3 LED Indications.............................................................................................................................................. 8
5.4 Keypad .......................................................................................................................................................... 8
5.5 Relay Identifier............................................................................................................................................... 8
5.6 Settings Mode................................................................................................................................................ 9
5.6.1 Settings Adjustment............................................................................................................................... 9
5.6.2 Settings And Displays............................................................................................................................ 9
5.7 Instruments Mode ........................................................................................................................................ 10
5.7.1 Hidden Instruments.............................................................................................................................. 11
5.8 Fault Data Mode ......................................................................................................................................... 11
6Diagrams ............................................................................................................................................................... 12
Figures
Figure 1 – MSCDN-MP2A Overview........................................................................................................................ 3
Figure 2 – Modular II Relay in E16 case with front panel open...............................................................................12
Figure 3 – Modular II Relay Rear View ...................................................................................................................12
Figure 4 – Menu Structure ......................................................................................................................................13
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MSCDN – MP2A Description of Operation
1 Introduction
MSCDN-MP2A
Thermal Overload and Open Circuit
Protection
C1
C2
R2
R1
R1
49
R2
49
50
AN1C1 - C3
AN2C1 - C3
Figure 1 – MSCDN-MP2A Overview
The MSCDN-MP2A relay provides wide bandwidth, true RMS phase by phase thermal Overcurrent protection and open
circuit protection for the damping resistors in a mechanically switched capacitor bank. Together with its sister units
MSCDN-MP1 and MP2B, this protection unit offers a complete solution for Main 1 and Main 2 protection of EHV
capacitor banks.
2 Hardware Description
2.1 General
The structure of the relay is based upon the Modular II hardware and software platform illustrated in Figure
2where the required cards plug in from the front after opening the front fascia. Modules are interconnected
by means of ribbon cable. The relay can be supplied in standard Epsilon case size E12 or E16. The
Modular II design provides commonality between products and spare parts across a range of protection
and control relays including Duobias, Ohmega, Delta, Tau and Iota.
Typical Configuration :
Analogue Inputs Status Inputs Output Relays Case
8 11 13 E12
Each analogue module requires three inputs; for measuring the CT secondary line currents from each of
the three phases A, B and C.
The unit consists of the following modules:
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MSCDN – MP2A Description of Operation
1) Two Wide Bandwidth Analogue Input modules (4 x I per module)
2) One Controller CPU module
3) One Power Supply and Basic I/O module
4) One Output relay/Status Input Module
5) One Front Fascia
2.2 Analogue Inputs
Two analogue modules are used in the case style E16. Each module consists of up to 4 channels of
current.
In order to ensure high accuracy true RMS measurements over a wide bandwidth and accurate phase and
slip frequency calculations, the current signals are sampled at 32 samples per cycle.
2.3 Status Inputs
The relay may be fitted with up to 27 status inputs. The user can program the relay to use any status input
for any function. A timer is associated with each input and a pickup time setting may be applied to each
input. In addition each input may be logically inverted to allow easy integration of the relay within the user
scheme. Each input may be mapped to any front Fascia LED and/or to any Output Relay contact. This
allows the Relay to act as panel indication for alarms and scheme status without having to use additional
external flagging elements.
2.4 Output Relays
The relay is fitted with up to 29 output relays, all of which are capable of handling circuit breaker tripping
duty. All relays are fully user configurable and can be programmed to operate from any or all of the control
functions. There are three relays on the Power Supply/Basic I/O module that have C/O contacts and 2 with
N/O contacts. Additional modules are fitted with 8 N/O contacts although N/C contacts are available as an
option.
In their normal mode of operation output relays remain energised for a minimum of 100msec and a
maximum dependent on the energising condition duration. If required, however, outputs can be
programmed to operate as latching relays. These latched outputs can be reset by either pressing the
TEST/RESET button, or by sending an appropriate communications command.
The operation of the contacts can be simply checked by using the Protection Healthy setting on the Output
Relay Menu to energise each relay in turn. Do not forget to reset this setting back to its correct value.
The output relays can be used to operate the trip coils of the circuit breaker directly if the circuit breaker
auxiliary contacts are used to break the trip coil current and the contact rating of the relay output contacts
is not exceeded for 'make and carry' currents.
With a failed breaker condition the current 'break' may be transferred to the relay output contacts and
where this level is above the break rating of the contacts an auxiliary relay with heavy-duty contacts should
be utilised.
2.5 Fascia LEDS
In the E12 and E16 case there are 32 user programmable LED flag indicators. By opening the front panel it
is possible to insert a strip into a slip in pocket, which provides legend information about the meaning of
each LED. The legend may be specified when ordering the relay or alternatively the user can create a
customized legend. The user can customise which LED is used for which purpose as well as being able to
program each LED as being latching or self –resetting.
2.6 Self Monitoring
The relay incorporates a number of self-monitoring features. Each of these features can initiate a
controlled reset recovery sequence, which can be used to generate an alarm output. In addition, the
Protection Healthy LED will give visual indication.
A watchdog timer continuously monitors the microprocessor. If the software fails to service the watchdog
timer the watchdog will time out and cause a reset.
The Output Relay modules are blocked in hardware if the watchdog timer expires.
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MSCDN – MP2A Description of Operation
Guard areas to intercept unintentional access surround the memory locations that control the Output
Relays.
Additionally the Output Relay modules incorporate an operational timeout feature, which prevents output
contacts from being held energised if the microprocessor fails to service them.
The voltage rails are also continuously supervised and the microprocessor is reset if any of the rails falls
outside of their working ranges. Any failure is detected in sufficient time so that the micro can be shut down
in a safe and controlled manner.
The program memory is supervised by a CRC check which runs continuously to verify its contents.
2.6.1 Protection Healthy/Defective
The normally closed contacts of relay 1 are used to signal protection defective, whilst the normally open
contacts are used to signal protection healthy. When the DC supply is not applied to the relay or a
problem is detected with the operation of the relay then this relay is de-energised and the normally
closed contacts make to provide an external alarm. When the relay has DC supply and it has
successfully passed its self-checking procedure then the Protection Healthy contacts are made and the
Protection Defective contacts are opened.
3 Protection Functions
3.1 Resistor R1 and R2 Thermal Overload (R1 49, R2 49)
The relay provides thermal overload protection for resistors R1 and R2. The elements, one per phase, use
32 samples/cycle to provide a flat frequency response up to 550 Hz and beyond. The elements are by
default disabled by a setting. An external status input may also be programmed to inhibit the elements. The
temperature of the protected equipment is not measured directly. Instead, thermal overload conditions are
detected by calculating the RMS of the current flowing in each phase of the resistor.
Should the RMS current rise above a defined level (the Overload Setting) for a defined time (the operating
time t), the system will be tripped to prevent damage.
Time to trip
()
⎭
⎬
⎫
⎩
⎨
⎧
×−
−
×τ= 2
2
2
P
2
I
II
ln
B
Ik
t
Where
IP= Previous steady state current level
IB= Basic current of resistor, typically the same as In
k = Multiplier resulting in the overload pickup setting k.IB
I = The measured resistor current
τ= Thermal time constant
Additionally, an alarm can be given if the thermal state of the system exceeds a specified percentage of
the protected equipment’s thermal capacity (Capacity Alarm).
The thermal state may be reset via an external status input.
3.2 Resistor R1 and R2 Open Circuit (50OC)
The resistor open circuit protection works by comparing the current in resistor R1 and resistor R2 on a
phase-by-phase basis. Because the resistors are the same value then the current through each resistor
should be equal. An instantaneous/time delayed Overcurrent element monitors the difference between the
currents on a phase-by-phase basis. If the element operates then the resistor, which has the LOWEST
current, is indicated on the Fascia leds. For an open circuit condition then this will be the faulty resistor.
However if there has been a short circuit in a resistor then this will not be true. The waveform records
should be downloaded to confirm the actual fault condition that has occurred.
An external status input may also be programmed to inhibit the element.
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MSCDN – MP2A Description of Operation
3.3 Trip Circuit Supervision
Status inputs on the relay can be used to supervise trip circuits while the associated circuit breakers (CB)
are either open or closed. Since the status inputs can be programmed to operate output contacts and
LED’s, alarms can be also generated from this feature.
To use the function set ‘Trip Cct Pickup Delay to the required value in the Reylogic Elements Menu and
then map the ‘Trip Circuit Fail’ settings in the Output Relay Menu and LED Menu as required.
See the Applications Guide for more details on the trip circuit supervision scheme.
4 Other Features
4.1 Metering
The metering feature provides real-time data available from the relay fascia in the ‘Instruments Mode’ or
via the communications interface.
The following displays are available:
RMS Resistor currents (primary and nominal)
RMS Resistor Open Circuit currents (nominal difference between R1 & R2)
Digital input status
Output relay status
Time and Date
4.2 Data Storage
4.2.1 General
Details of relay operation are recorded in three forms, namely Waveform records, Event records and
Fault Data records. All records are time and date stamped with a resolution of one millisecond.
4.2.2 Waveform Records.
The waveform record feature stores analogue and digital information for the current inputs, status inputs
and output relays and LED’s.
The waveforms are stored with a sampling resolution of 16 samples per cycle. The waveform recorder
has the ability to store records for the previous four trip operations of the relay. These are labelled 1-4
with 1 being the most recent record. This however, can be altered using the ‘Record Duration’ setting,
which offers the following selection:
•Four records of one-second duration.
•Two records of two seconds duration.
•One record of five seconds duration.
The waveform recorder will be triggered automatically when any protection element operates. It can also
be triggered by any of the following means:
•The ‘Trigger Storage” status input signal.
•The IEC870-5-103 communications interface.
The waveform recorder has a settable pre-fault triggering capability.
4.2.3 Event Records
The event recorder feature allows the time tagging of any change of state (Event) of the relay. As an
event occurs the actual event condition is logged as a record along with a time and date stamp to a
resolution of 1 millisecond. There is capacity for a maximum of 500 event records that can be stored in
the relay and when the event buffer is full any new record will over-write the oldest. The following events
are logged:
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MSCDN – MP2A Description of Operation
•Change of state of Output Relays.
•Change of state of Status Inputs.
•Change of Settings and Settings Group
•Change of state of any of the control functions of the relay.
4.2.4 Fault Recording
The led flag configuration, date and time of the last five faults are recorded for display via the Fascia
LCD.
Note: the real-time clock, waveform records and event records are all maintained, in the event of loss of
auxiliary D.C. supply voltage, by the backup storage capacitor. This capacitor has the ability to maintain
the charges on the real-time clock IC and the SRAM memory device for typically 2-3 weeks time
duration. This time, however, is influenced by factors such as temperature and the age of the capacitor
and could be shorter.
4.3 Time Synchronisation
Time and date can be set either via the relay fascia using appropriate commands in the System Config
menu or via an IRIG-B input or via the communications interface
4.3.1 IRIG-B Time Synchronisation
A BNC connector on the relay rear provides an isolated IRIG-B GPS time synchronisation port. The
IRIG-B input expects an modulated 3-6 Volt signal and provides time synchronisation to the nearest
millisecond.
4.3.2 IEC 60870-5-103 Time Synchronisation
Relays connected individually or in a ring or star configuration can be directly time synchronised using
the IEC 60870-5-103 global time synchronisation. This can be from a dedicated substation automation
system or from Reydisp Evolution Communications Support Software.
4.3.3 Real Time Clock Time Synchronisation
In the absence of IRIG-B and IEC60870 time synchronisation the relay contains a year 2000 compatible
real time clock circuit which maintains real time in the absence of DC supply (See Note).
4.4 Communications
Two fibre optic communication ports, COM 1 and COM 2b are provided at the rear of the relay, which give
superior EMC performance. An isolated RS232 port, COM 2a is provided at the front of the relay for local
access using a PC.
Communication is compatible with the IEC870-5-103 FT 1.2 transmission and application standards. For
communication with the relay via a PC (personal computer) a user-friendly software package, REYDISP
EVOLUTION, is available to allow transfer of the following:
Relay Settings
Waveform Records
Event Records
Fault Data Records
Instrument and meters
Control Functions
Communications operation is described in detail in Section 4 of this manual. For information about all
aspects of the communications protocol used in the Modular II range of relays see [2].
4.5 Settings Groups
Depending upon the relay model then up to four alternative setting groups are provided, making it possible
to edit one group while the relay protection algorithms operate using another ‘active’ group. An indication of
which group is being viewed is given by the ‘Gn’ character in the top left of the display. Settings that do not
indicate Gn in the top left corner of the LCD are common to all groups.
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MSCDN – MP2A Description of Operation
A change of group can be achieved either locally at the relay fascia or remotely via a communication
interface command.
4.6 Password Feature
The programmable password feature enables the user to enter a 4 character alpha code to secure access
to the relay settings. The relay is supplied with the password set to ‘NOT ACTIVE’, which means that the
password feature is disabled. The password must be entered twice as a security measure against accident
changes. Once a password has been entered then it will be required thereafter to change settings. It can,
however, be de-activated by using the password to gain access and by entering the password ‘NONE’.
Again this must be entered twice to de-activate the security system.
As soon as the user attempts to change a setting the password is requested before any setting alterations
are allowed. Once the password has been validated, the user is ‘logged on’ and any further changes can
be made without re-entering the password. If no more changes are made within 1 hour then the user will
automatically be ‘logged off’, re-enabling the password feature.
Note that the password validation screen also displays a numerical code. If the password is lost or
forgotten, this code should be communicated to Siemens and the password can be retrieved.
If the code is 1966067850 then 4 spaces have been entered as the password. This is caused by ENTER
being pressed three times on the Change Password setting screen. De-activate password using ‘NOT
ACTIVE’ as described above if this was set un-intentionally.
5 User Interface
The user interface is designed to provide a user-friendly method of entering settings and retrieving data from the relay.
The relay fascia includes a 20 character by 2 line, backlit, liquid crystal display (LCD), 32 light emitting diodes (LED) and
5 push buttons.
5.1 Liquid Crystal Display
The liquid crystal display is used to present settings, instrumentation and fault data in a textual format on a
2 lines by 20-character interface.
5.2 Back light Control
To conserve power the display backlighting is turned off if no push buttons are pressed for 5 minutes.
After an hour the whole display is de-activated. A setting within the “SYSTEM CONFIG MENU” allows the
timeout to be adjusted from 1 to 60 minutes and “OFF”, which means the backlight is always on.
5.3 LED Indications
The following indications are provided:
Protection Healthy – Green LED.
This LED is solidly illuminated to indicate that DC volts have been applied to the relay and that the relay is
operating correctly. If the internal relay watchdog detects a protection relay unhealthy condition then this
LED will continuously flash.
Programmable – Red LED.
An LED MENU is provided to map any output to any LED.
5.4 Keypad
Five pushbuttons are used to control the functions of the relay. They are labelled ×, Ø,ÖENTER and
CANCEL. Note that the Öbutton is also labelled TEST/RESET.
When the relay front cover is in place only the Øand Öbuttons are accessible. This allows only read
access to all the menu displays.
5.5 Relay Identifier
The Relay Identifier setting in the SYSTEM CONFIG MENU may be used to place a circuit identifier of up
to 16 alphanumeric characters onto the relay fascia e.g. BOLDON SGT1. This information is also returned
as part of the System Information command from Reydisp Evolution Communications Support Software.
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MSCDN – MP2A Description of Operation
5.6 Settings Mode
5.6.1 Settings Adjustment
The push buttons on the fascia are used to display the relay settings, display the operating signals, e.g.
currents, on the LCD and to reset the fault records and flag indication on the LCDs. There are five push
buttons marked read-up, read-down, enter, cancel, and right/test/reset only two of which are accessible
when the relay cover is on, namely read-down and right/rest/reset.
ØREAD DOWN / DECREMENT
In the Settings Display this push-button is used for scrolling down through a list of settings or signals.
In Settings Modification mode it is used for selecting the next value of (or decreasing) the displayed
setting or for deselecting a bit position in a particular control setting.
×READ UP / INCREMENT
In Settings Display or Signal Displays this push-button is used for scrolling back up through a list of
settings or signals.
In Settings Modification mode it is used for selecting the previous value of (or increasing) the displayed
setting or for selecting a bit position in a particular control setting.
ENTER
This push-button is used when the cover is removed to select between two modes of operation namely
Settings Display or Settings Modification.
When this push-button is pressed and a relay setting is being displayed part of the display will flash to
indicate that the setting being displayed can be modified by using the ×INCREMENT or Ø
DECREMENT keys on the facia.
When the required value of the setting has been established, it may be entered into the relay and acted
upon by pressing the ENTER key again.
CANCEL
This push-button is used when the cover is removed to return the relay display to its initial status. It can
be used to reject any alterations to the setting being modified provided the ENTER key has not been
pressed to accept the changes.
ÖTEST/RETEST
This push-button is used to reset the fault indication on the LEDs on the fascia it also acts as a lamp test
button because when pressed all of the LEDs will momentarily light up to indicate their correct operation.
The ØREAD DOWN and ×READ UP push-buttons may then be used to scroll through the various
signals.
5.6.2 Settings And Displays
The display menu structure is shown in Figure 4. This diagram shows the three main modes of display,
which are the Settings Mode, Instruments Mode and the Fault Data Mode.
When the relay is first energised the user is presented with the following message,
SETTINGS DEFAULTED
PRESS ENTER
Which shows that the relay has been set with the standard factory default settings. If this message is
displayed ENTER must be pressed to acknowledge this initial condition, the display will then indicate the
relay software variant. e.g.
MSCDN-MP2A
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MSCDN – MP2A Description of Operation
Pressing the ÖTEST/RESET key on this display initiates an LED test. Pressing ØREAD DOWN at this
display allows access to the three display modes, which are accessed in turn by pressing the Ö
TEST/RESET key.
The Settings Mode contains 15 setting sub-menu’s. These hold all of the programmable settings of the
relay in separate logical groups. The sub menus are accessed by pressing the key. This enters the sub
menu and presents a list of all the settings within that sub menu. Pressing ØREAD DOWN scrolls
through the settings until after the last setting in the group the next sub menu is presented. Access to this
group is via the same method as before. Pressing ØREAD DOWN will skip past a menu and present
the next one in the list. Note that all screens can be viewed even if the password is not known. The
password only protects against unauthorised changes to settings.
While viewing an editable screen pressing the ENTER key allows the user to change the displayed data.
A flashing character(s) will indicate the editable field. Pressing ×INCREMENT or ØDECREMENT
scrolls through the available setting values or, pressing ÖTEST/RESET moves right through the edit
fields. Note that all settings can be incremented or decremented using the ×INCREMENT or Ø
DECREMENT keys and they all wraparound so that to go from a setting minimum value to the maximum
value it is quicker to press the ØDECREMENT key, rather than scroll through every setting. Also, to
facilitate quicker setting changes an acceleration feature is available which if ×INCREMENT or Ø
DECREMENT are depressed and held, then the rate of scrolling through the setting values increases.
If ESCAPE/CANCEL is pressed during a setting change operation the original setting value is restored
and the display is returned to the normal view mode.
If changes are made to the setting value then pressing ENTER disables the flashing character mode and
displays the new setting value. This is immediately stored in non-volatile memory.
The next sections give a description of each setting in the relay. The actual setting ranges and default
values can be found in the Relay Settings section of this manual.
5.7 Instruments Mode
In INSTRUMENT MODE metering points can be displayed to aid with commissioning, the following meters
are available
INSTRUMENT DESCRIPTION
[ R1 METERS ]
--> press down <--
Start of resistor 1 meters
R1 Primary Currents
0.0 0.0 0.0 kA
Resistor 1 primary currents
R1 Nom Currents
0.00 0.00 0.00 xIn
Resistor 1 secondary nominal currents
R1 Thermal Status
0.0 0.0 0.0 %
Resistor 1 thermal status
[ R2 METERS ]
--> press down <--
Start of resistor 2 meters
R2 Primary Currents
0.0 0.0 0.0 kA
Resistor 2 primary currents
R2 Nom Currents
0.00 0.00 0.00 xIn
Resistor 2 secondary nominal currents
R2 Thermal Status
0.0 0.0 0.0 %
Resistor 2 thermal status
[ OPEN CCT METERS ]
--> press down <--
Start of resistor open circuit meters
Open Cct Currents
0.00 0.00 0.00 xIn
Resistor open circuit nominal currents
[ MISC METERS ]
--> press down <--
Start of miscellaneous meters
Status Inputs 1-16
---- ---- ---- ----
Displays the state of DC status inputs 1 to 161
Status Inputs 17-27
---- ---- ---
Displays the state of DC status inputs 17 to 271
Output Relays 1-16
---- ---- ---- ----
Displays the state of output relays 1 to 162
Output Relays 17-29
---- ---- ---- -
Displays the state of output relays 17 to 292
Time & Date
13/08/2002 10:16:11
Time and Date
1) Display is different when fewer status inputs are fitted
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MSCDN – MP2A Description of Operation
2) Display is different when fewer output relays are fitted
Note that meters not designated as primary or secondary values are usually displayed as multiples of
nominal
i.e. x In, 1 Amp or 5 Amp.
5.7.1 Hidden Instruments
At the “INSRUMENTS MODE” title screen, pressing ENTER and DOWN simultaneously reveals some
additional metering for calibration purposes. The reference channels as well as DC offsets may be
displayed along with the RMS values in raw ADC counts. The relationship between current and ADC
counts is 1.0 xIn = 600 counts.
5.8 Fault Data Mode
In “FAULT DATA MODE”, the time and date of relay operations are recorded together with a record of the
LED flag states.
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MSCDN – MP2A Description of Operation
6 Diagrams
Figure 2 – Modular II Relay in E16 case with front panel open
Figure 3 – Modular II Relay Rear View
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MSCDN – MP2A Description of Operation
RELAY IDENTIFIER
[ R1 METERS ]
--> PRESS DOWN <--
SETTINGS
MODE INSTRUMENTS
MODE FAULT DATA MODE
SYSTEM CONFIG MENU
ÖTO VIEW
[ R2 METERS ]
--> PRESS DOWN <--
[ OPEN CCT METERS ]
--> PRESS DOWN <--
FAULT 1
FAULT 5
LED TEST
NOTE : THE ARROWS IN THE DIAGRAM
REPRESENT THE KEY PRESSES REQUIRED
TO NAVIGATE THE MENU SYSTEM.
READ UP
READ DOWN
TEST/RESET
ENTER
CANCEL /
ESCAPE
[ MISC METERS ]
--> PRESS DOWN <--
COMMUNICATIONS MENU
ÖTO VIEW
LED MENU
ÖTO VIEW
Output Relays 1-5
1 _ _ _ _
Time & Date
16/07/2001 11:49:17
Status Inputs 1-3
_ _ _
CANCEL/ESCAPE
OUTPUT RELAY MENU
ÖTO VIEW
DATA STORAGE MENU
ÖTO VIEW
STATUS INPUT MENU
ÖTO VIEW
REYLOGIC CONTROL MENU
ÖTO VIEW
REYLOGIC ELEMENTS MENU
ÖTO VIEW
THERMAL MENU
ÖTO VIEW
CT/VT CONFIG MENU
ÖTO VIEW
OPEN CIRCUIT MENU
ÖTO VIEW
Figure 4 – Menu Structure
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MSCDN – MP2A Performance Specification
The copyright and other intellectual property rights in this document, and in any model or article produced from it
(and including any registered or unregistered design rights) are the property of Siemens Protection Devices
Limited. No part of this document shall be reproduced or modified or stored in another form, in any data retrieval
system, without the permission of Siemens Protection Devices Limited, nor shall any model or article be
reproduced from this document unless Siemens Protection Devices Limited consent.
While the information and guidance given in this document is believed to be correct, no liability shall be accepted
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©2011 Siemens Protection Devices Limited
MSCDN – MP2A
Capacitor unbalance protection
Document Release History
This document is issue 2011/10. The list of revisions up to and including this issue is:
Pre release
2011/10 Reference to 60Hz removed
2010/02 Document reformat due to rebrand
12/10/2004 R9 AC Voltage Input ratings added
VT Supervision function added
Status input minimum operate current corrected
Corrected operating time variation over frequency
28/02/2003 R8 IDMTL picks up at 105% of setting.
Three DTL elements are now available for Capacitor Unbalance
18/02/2003 R7 IDMTL O/C & E/F minimum operate time corrected
14/02/2003 R6 Operate time claims added for O/C and O/V elements
13/02/2003 R5 Removed incorrect references to drop-off timers on the status inputs.
10/02/2003 R4 All MP1 DO changed to ≥ 80%
Cx Unbalance Accuracy changed to ± 5% of setting or ± 0.01 In
21/01/2003 R3 Corrected element names
Added 59DT element
27/11/2002 R2 Resistor thermal overload characteristics added
Resistor open circuit characteristics added
24/10/2002 R1 Revision History Added.
Software Revision History
26/02/2006 2621H80002R9

MSCDN – MP2A Performance Specification
Contents
1Introduction ........................................................................................................................................................ 3
2Accuracy Reference Conditions ......................................................................................................................... 3
3Modular Ii Specification ...................................................................................................................................... 3
3.1 Environmental Withstand ......................................................................................................................... 3
3.2 Auxiliary Energizing Quantity ................................................................................................................... 5
3.3 A.C Current Inputs ................................................................................................................................... 5
3.4 A.C Voltage Inputs ................................................................................................................................... 5
3.5 Rated Frequency...................................................................................................................................... 5
3.6 Accuracy Influencing Factors ................................................................................................................... 6
3.7 Output Contacts ....................................................................................................................................... 6
3.8 Status inputs ............................................................................................................................................ 6
3.9 Auxiliary Timer Accuracy.......................................................................................................................... 7
3.10 Indication.................................................................................................................................................. 7
3.11 Settings And Configuration ...................................................................................................................... 7
3.12 Recording................................................................................................................................................. 7
3.13 Communications ...................................................................................................................................... 7
3.14 Irig-B Time Synchronisation ..................................................................................................................... 8
4Protection Elements ........................................................................................................................................... 8
4.1 Common Performance ............................................................................................................................. 8
4.2 87/50-x-x Overall Differential.................................................................................................................... 8
4.3 C1/2 50-x Capacitor Unbalance ............................................................................................................... 8
4.4 50N Cap Bank Phase Unbalance............................................................................................................. 8
4.5 R1/2 49 Resistor Thermal Overload......................................................................................................... 9
4.6 50 Resistor Open Circuit .......................................................................................................................... 9
4.7 49 Reactor Thermal Overload.................................................................................................................. 9
4.8 50 Backup Overcurrent ............................................................................................................................ 9
4.9 50N Backup Earth Fault ......................................................................................................................... 10
4.10 51 Backup Overcurrent, ......................................................................................................................... 10
4.11 51N Derived Earth Fault......................................................................................................................... 11
4.12 27 Undervoltage..................................................................................................................................... 12
4.13 59DT Definite Time Overvoltage ............................................................................................................ 12
4.14 59IT Inverse Time Overvoltage.............................................................................................................. 13
4.15 VT Supervision....................................................................................................................................... 13
©2011 Siemens Protection Devices Limited Chapter 2 Page 2 of 13

MSCDN – MP2A Performance Specification
1 Introduction
The following document defines the technical and performance specification of the MSCDN Series relays. MSCDN
relays are based upon the Siemens Reyrolle Modular II series of protection units.
Section 3 describes performance that is common to all Modular II protections.
Section 4 describes the performance of protection elements that may be fitted to MSCDN series relays. Therefore for
any one MSCDN series model, only the performance for those elements described in the Description of Operation,
as available in that model will be applicable.
Performance Data to:
IEC60255-6, IEC60255-6A and IEC60255-13.
Note:
Where performance is described as “X or Y”, then performance is “whichever is greater”, unless specified.
2 Accuracy Reference Conditions
General IEC60255
Parts 6, 6A & 13
Auxiliary Supply Nominal
Frequency 50 Hz
Ambient Temperature 20°C
3 Modular Ii Specification
3.1 Environmental Withstand
Temperature - IEC 60068-2-1/2
Operating range -10°C to +55°C
Storage range -25°C to +70°C
Humidity - IEC 60068-2-3
Operational test 56 days at 40°C and 95% RH
Transient Overvoltage –IEC 60255-5
Between all terminals and earth or between any two
independent circuits without damage or flashover
5kV 1.2/50µs 0.5J
Insulation - IEC 60255-5
Between all terminals and earth 2.0kV rms for 1 min
Between independent circuits 2.0kV rms for 1 min
Across normally open contacts 1.0kV rms for 1 min
High Frequency Disturbance -
IEC 60255-22-1 Class III
Variation
2.5kV Common (Longitudinal) Mode ≤5%
1.0kV Series (Transverse) Mode ≤5%
Electrostatic Discharge -
IEC 60255-22-2 Class IV
Variation
8kV contact discharge ≤5%
Conducted & Radiated Emissions -
EN 55022 Class A (IEC 60255-25)
Conducted 0.15MHz – 30MHz
Radiated 30MHz – 1GHz
Conducted Immunity -
(IEC 61000-4-6; IEC 60255-22-6)
Variation
©2011 Siemens Protection Devices Limited Chapter 2 Page 3 of 13

MSCDN – MP2A Performance Specification
0.15MHz – 80MHz 10V rms 80% modulation ≤5%
Radiated Immunity -
IEC60255-22-3 Class III
Variation
80MHz to 1000MHz, 10V/m
80% modulated
≤5%
Fast Transient – IEC 60255-22-4 Class IV
Variation
4kV 5/50ns 2.5kHz repetitive ≤5%
Surge Impulse -
IEC 61000-4-5 Class IV; (IEC 60255-22-5)
Variation
4KV Line-Earth (O/C Test voltage +10%)
2KV Line-Line
≤10
Vibration (Sinusoidal) –IEC 60255-21-1 Class 1
Variation
Vibration response 0.5gn ≤5%
Vibration endurance 1.0gn ≤5%
Shock and Bump–IEC 60255-21-2 Class 1
Variation
Shock response 5 gn 11ms ≤5%
Shock withstand 15 gn 11ms ≤5%
Bump test 10 gn 16ms ≤5%
Seismic – IEC 60255-21-3 Class 1
Variation
Seismic Response 1gn ≤5%
Mechanical Classification
Durability In excess of 106operations
©2011 Siemens Protection Devices Limited Chapter 2 Page 4 of 13

MSCDN – MP2A Performance Specification
3.2 Auxiliary Energizing Quantity
DC Power Supply
Nominal Operating Range
30V 24V to 37.5V dc
50/110V 37.5V to 137.5V dc
220/250V 175V to 286V dc
Auxiliary DC Supply – IEC 60255-11
Allowable superimposed ac component ≤12% of DC voltage
Allowable breaks/dips in supply (collapse to zero from
nominal voltage)
≤20ms
D.C. Burden
Quiescent (Typical) 15 Watts
Max 27 Watts
3.3 A.C Current Inputs
1 Amp and 5 Amp current inputs are both available on the rear terminal blocks for most functions except Capacitor
Unbalance.
3.3.1 Thermal Withstand
Continuous and Limited Period Overload
AC Current Inputs
3.0 x In Continuous
3.5 x In for 10 minutes
4.0 x In for 5 minutes
5.0 x In for 3 minutes
6.0 x In for 2 minutes
250A for 1 second
625A peak for 1 cycle
3.3.2 A.C. Burden
A.C. Burden
1A tap ≤ 0.1 VA
5A tap ≤ 0.3 VA
NB. Burdens are measured at nominal rating.
3.4 A.C Voltage Inputs
.Thermal Withstand
Continuous Overload
AC Voltage 320Vrms (452Vpk)
3.4.1 A.C. Burden
A.C. Burden
110Vrms ≤ 0.05 VA
63.5Vrms ≤ 0.01 VA
3.5 Rated Frequency
Frequency: 50Hz
Frequency
Range 47Hz to 52Hz
Setting variation ≤5%
Operating time variation ≤5% or 5ms
©2011 Siemens Protection Devices Limited Chapter 2 Page 5 of 13